Electronic apparatus and display panel fixed structure

ABSTRACT

An electronic apparatus of the present invention has a display panel incorporating therein a display screen and a back cover that covers the display panel. The display panel is fixed to the back cover via a fixing part. The back cover has a positioning pin standing on the same central axis as a mounting hole formed in the display panel. The fixing part has a positioning hole that engages the positioning pin and a screw hole on the same central axis as the positioning hole. A screw is screwed into the screw hole of the fixing part through the mounting hole of the display panel.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese Patent Application No.2004-249256 filed on Aug. 27, 2004, the entire disclosure of which isincorporated by reference.

FIELD OF THE INVENTION

The present invention relates to an electronic apparatus provided with adisplay panel having a screen display therein and to a fixed structureof the display panel.

BACKGROUND OF THE INVENTION

Typically, electronic apparatus such as notebook or laptop computershave a first unit having a keyboard that is coupled by hinges to asecond unit having a display screen, such that the two units can beopened and closed relative to each other. When the apparatus is used,the second unit is opened, and when it is not used, the second unit isclosed such that the display screen lies on the keyboard. This type ofapparatus is well known as a notebook personal computer (hereinafterreferred to as a notebook PC).

Another type of portable computer includes a display screen, wherein thedisplay screen is configured to recognize a stylus or pen-like devicethat is placed close to or in contact with the screen to enable userinput. This type of apparatus is well known as a tablet personalcomputer (hereinafter referred to as a tablet PC).

Recently, convertible tablet/notebook computers have become availablewith the first unit and the second unit coupled through a two-axiscoupling device which allows rotation of the second unit in twodirections relative to the first unit. This configuration allows thecomputer to be used either as a notebook PC with the display screenprojecting upward from the keyboard, or as a tablet PC with the displayscreen resting facing up on the keyboard (refer to Japanese PatentApplication Publication No. 11-312876).

Such electronic apparatus are usually provided with a display panelhaving a large display screen. The display panel is generally fixed tothe apparatus in the following manner. A mounting hole is formed in thedisplay panel whereas a boss having a screw hole in the center is formedon the back cover. The display panel is then fixed by inserting a screwthrough the mounting hole into the screw hole formed on the boss.

A fixing member or supporting member of elastic material which is usedfor fixing a display panel is disclosed in Japanese Patent ApplicationPublications No. 2000-47754 and No. 2002-328622. The elastic material isused to protect the display panel from being damaged by a strong force.

Display panels made by different manufactures have the respectivemounting holes in different positions. If only one type of back cover isused and needs to accept two or more types of display panels made bydifferent manufactures, the back cover must have two or more bosses witha screw hole for the mounting holes of these different types of displaypanels. The bosses are formed in the different positions of the backcover.

However, if the back cover has this structure, a boss formed for onetype of display panel interferes with other type of display panel madeby other manufacturer. Due to such interference, this other type ofdisplay panel cannot be fixed to the back cover.

Even if only a particular display panel made by a particularmanufacturer is adopted and a boss is formed on the back cover so as tocorrespond to a mounting hole of the display panel, the boss interfereswith components to be positioned and fixed other than the display panel.

These situations can be avoided by forming a boss on the back cover inthe position that does not correspond to the position of a mounting holeof the display panel, and by using a fixing part to connect the boss andthe mounting hole that are positioned apart.

However, as pointed out by Japanese Patent Application Publications No.2000-47754 and No. 2002-328622, if the fixing part is used for fixing,there arises a problem that blurred images are displayed due to adimensional deviation, which needs to be addressed.

SUMMARY OF THE INVENTION

The present invention has been made in view of the above circumstancesand provides an electronic apparatus having a structure in which adisplay panel is fixed by suppressing a dimensional deviation to asufficiently low level even if the position of a boss formed on the backcover and the position of a mounting hole formed in the display panel donot coincide. The present invention also provides a display panel fixedstructure used in the electronic apparatus.

An electronic apparatus of the present invention includes a displaypanel having a display screen and a cover for covering the displaypanel, wherein:

the display panel has a first mounting hole for accepting a fastener;

the cover has a first boss on which a first fastener hole is formed andwhich is formed in a position off the first mounting hole, and the coverfurther has a positioning projection that projects on the same centralaxis as the first mounting hole; and

the electronic apparatus includes a fixing member in which are formed asecond mounting hole that is fixed by a fastener to the first fastenerhole of the first boss, a positioning hole in which the positioningprojection is engaged, and a second fastener hole that is formed on thesame central axis as the positioning hole and fixed by a fastener to thefirst mounting hole.

According to the present invention, the cover of the electronicapparatus has a positioning projection that projects on the same centralaxis as the first mounting hole of the display panel. On the other hand,the fixing member of the electronic apparatus has a positioning hole inwhich the positioning projection is engaged, and the fixing memberfurther has a fastener hole that is formed on the same central axis asthe positioning hole and fixed by a fastener to the first mounting hole(of the display panel). Thus, even if a boss of the back cover forfixing the display panel is formed in a position that does not match theposition of a mounting hole of the display panel, it is possible to fixthe display panel with sufficiently high position precision, accordingto the present invention.

Further, in the electronic apparatus of the present invention, the covermay be capable of accepting a display panel having a third mounting holethat is formed in a position different from the first mounting holeinstead of the first mounting hole, and the cover may include a secondboss that has a third fastener hole on the same central axis as thethird mounting hole.

In this manner, the electronic apparatus of the present invention may beconfigured such that the cover can accept two or more types of displaypanels having the respective mounting holes formed in differentpositions and the cover has the second boss to which a display panel ofother type is directly screwed.

Furthermore, in the electronic apparatus of the present invention, thefixing member may have a bent portion having two plates bent to faceeach other, and the positioning hole may be formed in the lower plate ofthe bent portion and the second fastener hole may be formed in the upperplate of the bent portion. Still furthermore, in the electronicapparatus of the present invention, the fixing member may have a throughhole of which lower portion is used as the positioning hole and of whichupper portion is used as the second fastener hole.

The display panel can be fixed to the cover with high position precisionby using the above fixing members.

A display panel fixed structure according to the present invention isused in an electronic apparatus provided with a display panel, thedisplay panel including a display screen and a cover for covering thedisplay panel, wherein:

the cover has a first boss on which a first fastener hole is formed andwhich is formed in a position off a first mounting hole formed in thedisplay panel for accepting a fastener, and the cover further has apositioning projection that projects on the same central axis as thefirst mounting hole; and

the display panel fixed structure includes a fixing member in which areformed a second mounting hole that is fixed by a fastener to the firstfastener hole of the first boss, a positioning hole in which thepositioning projection is engaged, and a second fastener hole that isformed on the same central axis as the positioning hole and fixed by afastener to the first mounting hole.

Further, in the display panel fixed structure of the present invention,the cover may be capable of accepting a display panel having a thirdmounting hole that is formed in a position different from the firstmounting hole instead of the first mounting hole, and the cover mayinclude a second boss that has a third fastener hole on the same centralaxis as the third mounting hole.

Furthermore, in the display panel fixed structure of the presentinvention, the fixing member may have a bent portion having two platesbent to face each other, and the positioning hole may be formed in thelower plate of the bent portion and the second fastener hole may beformed in the upper plate of the bent portion. Still furthermore, in thedisplay panel fixed structure of the present invention, the fixingmember may have a through hole of which lower portion is used as thepositioning hole and of which upper portion is used as the secondfastener hole.

As described above, the present invention makes it possible to fix thedisplay panel to the back cover by suppressing a dimensional deviationto a sufficiently low level even if the position of the boss formed onthe back cover and the position of the mounting hole formed in thedisplay panel do not coincide with each other.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective illustration of an electronic apparatusaccording to an embodiment of the present invention;

FIG. 2 is a perspective illustration of the electronic apparatus shownin FIG. 1 in which the optical disk drive is in the open status;

FIG. 3 is a perspective illustration of a port replicator attached tothe electronic apparatus shown in FIGS. 1 and 2;

FIG. 4 is a perspective illustration of the electronic apparatus of thepresent invention in the open status, coupled to the port replicatorshown in FIG. 3;

FIG. 5 is a perspective illustration showing the electronic apparatus ofthe present invention in the closed status, coupled to the portreplicator;

FIG. 6 is a perspective illustration showing the second unit rotated by90° relative to the normal open position;

FIG. 7 is a perspective illustration showing the second unit lying onthe first unit with the display screen facing upward;

FIG. 8 is a plan view showing an engagement unit provided in the firstunit;

FIGS. 9A and 9B are perspective views of an attachment unit provided inthe second unit;

FIGS. 10A and 10B are perspective views of a fixture member of theattachment unit.

FIGS. 11A and 11B show a cutaway view of a cover member of theattachment unit;

FIGS. 12A and 12B are perspective illustrations of another embodiment ofan attachment unit;

FIGS. 13A and 13B show a fixture member of the attachment unit of FIGS.12A and 12B;

FIGS. 14A and 14B show a cutaway view of a cover member of theattachment unit of FIGS. 12A and 12B;

FIG. 15 is an exploded view showing the procedure of assembling theattachment unit;

FIG. 16 is an enlarged view of the vicinity of the coupling section ofthe electronic apparatus shown in FIG. 1;

FIG. 17 shows the status in which the second unit is rotated by 180° toallow the back of the second unit to face the keyboard switched from thestatus shown in FIG. 16;

FIGS. 18A, B and C show views in which the second unit is opened by 180°relative to the first unit;

FIG. 19 shows the upper right portion of the back cover and the displaypanel of the second unit of the electronic apparatus shown in FIG. 1;

FIG. 20 shows the same portion as FIG. 19, and shows the antenna and thefixing part in the normal positions;

FIG. 21 shows the same portion as FIGS. 19 and 20 and the antenna, thefixing part, and the display panel are arranged in the normal positions;

FIG. 22 shows the structure of the lower left portion of the displaypanel;

FIG. 23 shows the structure of the lower left portion of the displaypanel;

FIG. 24 shows the structure of the lower left portion of the displaypanel;

FIG. 25 shows the structure of the lower left portion of the displaypanel;

FIG. 26 shows a part of a bottom cover of the first unit of theelectronic apparatus shown in FIG. 1, and a circuit substrate arrangedon the bottom cover;

FIG. 27 is a block diagram of the DC-DC converter;

FIG. 28 shows the relative positions of the bottom cover and theexternal coil viewed from the bottom cover;

FIG. 29 is a block diagram of a system for controlling the optical diskdrive of the electronic apparatus shown in FIG. 1;

FIG. 30 is a flowchart of a program operating in the CPU of the mainsystem to control the optical disk drive of the electronic apparatus;

FIG. 31 shows a screen display for enabling the user to control use ofthe optical disk drive;

FIG. 32 shows a screen display when the optical disk drive is disabled;

FIGS. 33A and 33B are further screen displays showing that the opticaldisk drive is disabled;

FIGS. 34A and 34B show examples of screen displays for enabling use ofthe optical disk drive;

FIG. 35 shows an example of the screen displayed when use of the opticaldisk drive is enabled in response to the query displayed in FIG. 34B;

FIG. 36 shows an example of the screen displayed informing that theoptical disk drive 26 is enabled; and

FIG. 37 shows the warning screen when the function of prohibiting theuse of optical disk drive is overridden in the tablet mode.

DETAILED DESCRIPTION

An embodiment of an electronic apparatus according to the presentinvention is explained below.

[Appearance]

FIG. 1 is a perspective illustration of the appearance of the electronicapparatus of the present invention.

An electronic apparatus 10 includes a first unit 20, and a second unit30. These first unit 20 and second unit 30 are coupled through atwo-axis coupling section 40 such that the second unit 30 can be openedand closed in the direction of the arrow A-A to the first unit 20, andcan be rotated in the direction of the arrow B-B (on the verticalrotation axis). In FIG. 1, the second unit 30 is open relative to thefirst unit 20 (open status).

The first unit 20 includes on an upper cover 73 a keyboard 21, a trackpad 22, a left click button 23, a right click button 24, and anengagement unit 25 for engaging the second unit 30 when the second unit30 is closed. The engagement unit 25 is provided with an engagement hole251 for the fixture of the second unit 30, and an engagement releasebutton 252 for releasing the engagement of the fixture in the engagementhole. The details of the engagement unit 25 are described later. On aside of the first unit 20, an open/close cover 261 of an optical diskdrive 26 for accessing an optical disk such as a CD, a DVD, etc. Theopen/close cover 261 is provided removed from the optical disk drive 26.

FIG. 2 is a perspective illustration of the electronic apparatus of FIG.1 showing the optical disk drive 26 in the open position.

When the eject button 262 provided on the open/close cover 261 of theoptical disk drive 26 is pressed, the tray of the optical disk drive 26can be projected as shown in FIG. 2, so that the optical disk can beinserted or removed.

Referring back to FIG. 1, the second unit 30 of the electronic apparatus10 shown in FIG. 1 includes a front cover 63 having a display window631. This side of the second unit 30 will be referred to as the “front”side. In the display window 631, a display screen 611 of a built-indisplay panel 61 (refer, e.g., to FIGS. 19 to 21) is shown. Thecombination of the display screen 611 and the display window 631 issometimes referred to as display screen 31. The second unit 30 isprovided with buttons 32 adjacent to the display screen 31. Above thedisplay screen 31 is an attachment unit 33 provided with a fixture forengaging the engagement unit 25 of the first unit 20 when the secondunit 30 is closed. As described in detail later, the attachment unit 33includes two fixtures. In FIG. 1, one fixture 332 a of the two fixturesis projected from an aperture 331 a on the front of the second unit 30.

FIG. 3 is a perspective view of a port replicator 50 for use with theelectronic apparatus 10 shown in FIG. 2. FIG. 4 shows the first unit 20of the electronic apparatus 10 coupled to the port replicator 50 withthe second unit 30 in the open position.

As shown in FIG. 3, the port replicator 50 is provided with a connector51 for electrically coupling to the first unit 20, and has a variety ofI/O terminals on the back (not shown). The connector 51 of the portreplicator 50 is coupled to a mating connector (not shown) provided atthe bottom of the first unit 20, thereby providing a signal between thefirst unit 20 and the port replicator 50. Although various I/O terminalsare provided in the first unit 20, the port replicator 50 has thefunction of extending the number of the I/O terminals. Variousperipheral devices may be connected to the I/O terminals of the portreplicator 50, thereby adding the functionality of the electronicapparatus 10. Thus, the first unit is simply placed on the portreplicator 50 as shown in FIG. 4 to provide the desired addedfunctionality. However, when it is not necessary to use the peripheraldevices provided by the port replicator 50, the electronic apparatus 10may be removed from the port replicator 50 and can be used as either inthe notebook PC mode or the tablet PC mode.

FIG. 5 shows the electronic apparatus 10 placed on the port replicatorwith the second unit 30 in the closed position.

The second unit 30 is laid on the first unit 20 with the display screen31 (refer to FIG. 1) facing the first unit 20, which is referred to asthe first closed status.

As shown in FIG. 5, the attachment unit 33 for engagement in the firstunit 20 in the closed status has an aperture 331 b on the back of thesecond unit 30. The details of the attachment unit 33 are describedlater.

FIG. 6 shows the electronic apparatus 10 with the second unit 30 that isrotated by 90° relative to the front side of the first unit 20. Thesecond unit 30 can be further rotated such that the display screen 31faces away from the keyboard 21.

The second unit 30 can then be rotated down into a position such thatthe display screen 31 faces upward when the two units are closed, asshown in FIG. 7. In this position, the display is opposite the keyboard21 and is visible to the user. This position is referred to as thesecond closed status. In the second closed status, the electronicapparatus 10 may be used as a tablet PC, and this is sometimes referredto herein as the tablet mode. Normally, in the tablet mode, theelectronic apparatus 10 is not coupled to the port replicator 50 (referto FIG. 3).

The display screen 31 has a pen input function for detecting the contactof a pen or the close position of a pen. Normally, when the electronicapparatus 10 is in the tablet mode it is carried in the user's arm, andthe hand of the other arm holds a pen (not shown), which is used toprovide input directly to the display screen. Normally, in the tabletmode the image on the display screen 31 is rotated by 90° relative tothe display provided in the notebook PC mode shown in FIG. 1.

When the electronic apparatus 10 is in the tablet mode as shown in FIG.7, the aperture 331 a of the attachment unit 33 on the second unit 30faces upward. The aperture 331 a is positioned adjacent to the displayscreen 31, and the aperture 331 a is also shown in FIG. 1. As shown inFIG. 1, when the electronic apparatus 10 is in the notebook mode, thefirst fixture 332 a projects from the aperture 331 a. In contrast, whenthe electronic apparatus 10 is in the tablet mode, no fixture projectsfrom the aperture 331 a as shown in FIG. 7, instead, another fixtureprojects from the aperture 331 b (refer to FIG. 5) on the back of thesecond unit 30, and the fixture is engaged in the engagement hole 251shown in FIG. 1. In the engaged status the second unit 30 is securelyheld by the first unit 20 until the engagement release button 252 isoperated. When the second unit 30 is engaged in the manner shown in FIG.7, the electronic apparatus 10 can be used as a tablet PC having aplanar housing.

[Engagement Unit and Attachment Unit]

FIG. 8 shows an embodiment of the engagement unit 25 provided in thefirst unit (refer to FIG. 1).

The engagement hole 251 is formed in the engagement unit 25. At thecenter of the engagement hole 251, an engagement detent 253 is extendedfrom a side into the engagement hole 251. Adjacent to the engagementhole 251, the engagement release button 252 is formed on the sideopposite to the detent. The engagement release button 252 and theengagement detent 253 are integrally formed as one piece (hereinafterreferred to as an engagement part). At the center of the part, theengagement hole 251 is formed. The engagement part is slidably held in aframe part 254, and the engagement part is urged by a spring 255 towardsthe direction of the release button 252.

The top surface of the engagement detent 253 is tapered. When a fixturesuch as fixture 332 a or fixture 332 b (shown, for example in FIGS. 9Aand 9B) of the attachment unit 33 enters the engagement hole 251, thefixture exerts force on the tapered portion of the engagement detent253, causing the spring 255 to compress such that the engagement partslides out of the way of the fixture. As shown in FIGS. 9A and 9B, thefixtures have an aperture or hole formed therein which is sufficientlylarge to accept the engagement detent 253. As the fixture travels intothe engagement hole 251, the hole in the fixture becomes aligned withengagement detent. This allows the spring 251 to release causing thedetent 253 to enter the hole in the fixture and securely engage theengagement detent 253. The fixture is thereby locked in position by theengagement unit 25. When the engagement release button 252 is pressed,the engagement part compresses the spring 255 and moves the detent 253out of the hole in the fixture. The fixture may then be removed from theengagement hole 251.

FIGS. 9A and 9B show the attachment unit 33 provided in the second unit30, including a fixture. FIGS. 10A and 10B show a fixture member of theattachment unit 33 shown in FIGS. 9A and 9B. FIGS. 11A and 11 b show acover member of the attachment unit 33.

The attachment unit 33 is composed of a fixture member 332 and a covermember 333. First, the fixture member 332 is explained below.

FIGS. 10A and 10B respectively show the two sides of the fixture member332 which are substantially identical.

The fixture member 332 is provided with the first fixture 332 a and thesecond fixture 332 b which are 90° apart. Between the fixtures is aprojection 332 c which serves as a rotation axis. Two substantiallyidentical concave sections 332 d and 332 e are formed at an equaldistance from the projection 332 c. The concave sections 332 d and 332 eare connected by an arcuate groove 332 f which is shallower than the twoconcave sections 332 d and 332 e.

Now the cover member 333 is explained below.

FIG. 11 a shows a cutaway view of the cover member. FIG. 11B shows theinner side of the cover member of the cut off portion.

The cover member 333 has two spaced apart, parallel plate sections 333 aand 333 b. Each of the plate sections 333 a and 333 b contains a supporthole 333 c to engage the projection 332 c of the fixture member 332 suchthat the fixture member 332 can be rotated within the cover. A convexsection 333 d is formed on interior of the two plate sections 333 a and333 b. When the fixture member 332 is position in the cover member 333,the convex section 333 d engages either the first concave section 332 dor the second concave section 332 e, or during the rotation of thefixture member 332, the convex section 333 d is located within thearcuate groove 332 f. On both ends of the cover member 333, a tipsection 333 g having an attachment hole is provided.

The fixture member 332 is positioned within the cover member 333, byinserting it between the two plate sections 333 a and 333 b of the covermember 333. The two plate sections 333 a and 333 b expand allowing thefixture member 332 to enter the space between the two plate sections 333a and 333 b, and the projection 332 c enters the support hole 333 c.Simultaneously, the convex section 333 d provided inside the two platesections 333 a and 333 b is engaged in the first concave section 332 dor the second concave section 332 e of the fixture member 332. Thefixture member 332 can be rotated by 90°. During rotation, the convexsection 333 d of the cover member 333 travels in the arcuate groove 332f. Since the arcuate groove 332 f is shallower than the first concavesection 332 d or the second concave section 332 e, the two platesections 333 a and 333 b are deflected slightly outward during therotation. The user can feel the fixture member “click” into positionwhen the convex section 333 d enters the first concave section 332 d orthe second concave section 332 e. Since the concave sections are deeperthan the arcuate groove 332 f, the cover member 333 holds the fixturemember 332 in position when the convex section 333 d is engaged ineither first concave section 332 d, 332 e. Thus, in order to rotate thefixture member 332 it is necessary to apply a slight force.

The two apertures 331 a and 331 b shown in FIGS. 9A, 9B, 12A and 12B areformed on the sides of the cover member 333 by the plate sections 333 aand 333 b.

By rotating the fixture member 332 as previously described, either thefirst fixture 332 a or second fixture 332 b will extend from theaperture 331 a or 331 b as shown. The other fixture that does notproject outwardly is retained in the space between the two platesections 333 a and 33 b.

When the first fixture 332 a is operated and rotated from the positionof FIG. 9A, the convex sections 333 d shown in FIG. 11 are removed fromthe first concave section 332 d shown in FIG. 10 with the feeling ofclick, the convex section 333 d travels on the arcuate groove 332 f.After rotating 90° and the convex sections 333 d engage in the secondconcave section 332 e shown in FIGS. 10A and 10B and click intoposition. At this time, as depicted in FIG. 9B, the second fixture 332 bprojects from the aperture 331 b and the first fixture 332 a is storedbetween the two plate sections 333 a and 33 b.

In order to allow the electronic apparatus 10 in the open status shownin FIG. 4 to enter the first closed status shown in FIG. 5, the fixturemember is rotated such that the first fixture 332 a of the fixturemember 332 of the attachment unit 33 projects from the aperture 331 a ofthe display screen 31 (refer to FIG. 4), and the second unit 30 isrotated onto the top of the first unit 20 such that the display screen31 faces the first unit 20. In this position, the first fixture 332 aextends into the engagement hole 251 of the engagement unit 25 providedin the first unit 20, the first fixture 332 a is engaged in theengagement unit 25 as explained above by referring to FIG. 8. The secondunit 30 is held securely in position until it is released by theengagement release button 252.

To use the electronic apparatus 10 shown in FIG. 1 in the second closedstatus (tablet PC mode) shown in FIG. 7, the fixture is rotated suchthat the second fixture 332 b of the fixture member 332 of theattachment unit 33 projects from the aperture 331 b (refer to FIG. 5) onthe back of the second unit 30. The second unit 30 is rotated such thatthe display screen 31 faces upward from the first unit 20, and furtherrotated onto the top of the first unit 20 such that the back of thesecond unit 30 faces the first unit 20. In this position, the secondfixture 332 b extends into the engagement hole 251 of the engagementunit 25, thereby securely fixing the apparatus in the tablet mode. Thus,the first unit 20 can be securely held by the fixture member 332 ineither the first or second closed positions by rotation of the fixturemember. Rotation of the fixture member can be performed by a simplemanipulation of the user's fingers, thereby allowing use in either thenotebook PC mode and the tablet mode using a single hand.

Described below is another embodiment of the attachment unit.

FIGS. 12A and 12B show opposing sides of another embodiment of anattachment unit of the present invention. FIGS. 13A and 13B showopposing sides of the fixture member forming the attachment unit. FIGS.14A and 14B show a cover member of the attachment unit. FIG. 15 is anexploded view showing how the attachment unit is assembled.

In this embodiment, the components corresponding to those of theattachment unit explained by referring to FIGS. 9 to 11 are assigned thereference numerals assigned in FIGS. 9 to 11, and the features differentfrom the attachment unit shown in FIGS. 9 to 11 are mainly explainedbelow.

FIGS. 12A and 12B show an attachment unit similar to the one shown inFIGS. 9A and 9B. To the extent the alternative embodiment is the same infunction or design as described above, the applicable description is notrepeated. However, FIGS. 12A and 12B show a difference in the headsection 334 a of an axis member 334 (refer to FIG. 15). The axis member334 is described later.

On the fixture member 332, a bearing hole 332 g for insertion of theaxis member 334 (refer to FIG. 5) is formed between the first fixture332 a and the second fixture 332 b. On the side depicted by FIG. 13A, acircular concave section 332 h in which a flat washer 335 (refer to FIG.15) is engaged is formed. On the side indicated by FIG. 13B, two firstconcave sections 332 d and two second concave sections 332 e are formedaround the bearing hole 332 g. These two first concave sections 332 dand two second concave sections 332 e are coupled by the arcuate groove332 f shallower than the first concave section 332 d and the secondconcave section 332 e. The first concave section 332 d and the secondconcave section 332 e are formed in two units, and are formed only onone side of the fixture member 332. Otherwise, they operate in a mannersimilar to that previously described.

FIGS. 14A and 14B show the cover member of the attachment unit in thisalternative embodiment. For illustration purposes, FIG. 14A shows acutout in a plate section 333 b, and FIG. 14B shows the inner side ofthe plate section 333 b which has been cutout.

In the alternative embodiment, there are two the convex sections 333 din the plate section 333 a which engage either the first concave section332 d or the second concave section 332 e (see FIG. 13). Grooves 333 kare formed adjacent to both sides of the support hole 333 c inside theother plate section 333 b to moderate the spring effect of a wavy washer336 (refer to FIG. 15) by slightly deforming the part sandwiched betweenthe grooves 333 k when the fixture member 332 is rotated.

When assembling the attachment unit, the fixture member 332, the flatwasher 335, and the wavy washer 336, which functions as a spring, areenclosed between the cover members 333 as shown in FIG. 15. The fixturemember 332 is arranged with the side shown in FIG. 13B facing the platesection 333 a. The axis member 334 is then inserted through thecomponents and the tip section 334 b of the axis member 334 is engagedin an E ring 337. The E ring prevents the axis member 334 from slipping.

In this embodiment, the wavy washer 336 works as a spring, so that it isnot necessary to depend on the spring force of the cover member 333,thereby improving the flexibility in selection and design of materials.

[Open/Close Sensor]

When the electronic apparatus 10 is in the notebook PC mode shown inFIG. 1 and in the first closed status shown in FIG. 5 with the powerturned on, the internal circuit in the apparatus causes it to enter“standby” status. On the other hand, when the electronic apparatus 10 isin the notebook PC mode shown in FIG. 1 and in the second closed statusshown in FIG. 7, such that it enters the tablet mode, the orientation ofthe image on the display screen 31 in the notebook PC mode is rotated by90°. To realize these functions, the electronic apparatus 10 shown inFIG. 1 is provided with an open/close sensor for detecting whether theapparatus is opened or closed, as described below.

FIG. 16 is an enlarged view of the vicinity of the coupling section 40of the electronic apparatus 10 shown in FIG. 1.

FIG. 16 shows the electronic apparatus 10 in the first closed statuswith the display screen 31 facing the keyboard 21, without a cover atthe back portion of the keyboard 21 and the lower portion of the displayscreen.

A circuit substrate 28 is provided with a first magnetic sensor 271 anda second magnetic sensor 272 adjacent to the rotation axis 41. In thisstructure, both the first magnetic sensor 271 and the second magneticsensor 272 are positioned on a circuit substrate 28 to facilitatepositioning of the sensors and, thereby, reducing the cost ofmanufacture.

The circuit substrate 28 is also provided with a connector 273 fortransmission of a detected signal of the first magnetic sensor 271 andthe second magnetic sensor 272 to computer circuitry. The connector 273is combined with a connector 29 connected to the tip of the lead linefrom the circuit in the first unit first unit 20. Signals from the firstmagnetic sensor 271 and the second magnetic sensor 272 are transmittedto the circuitry through the connectors 273 and 29.

A first magnet 341 is arranged in the position below the display screen31 of the second unit 30, which is positioned over the first magneticsensor 271 when the second unit 30 is closed in the first closed status,as shown in FIG. 5. The first magnet 341 is in a case 341 a with anopening which allows it to provide a strong magnetic force in thedirection of the display screen 31.

By changing the electronic apparatus 10 from the open status shown inFIG. 1 to the first closed status shown in FIG. 5, the first magnet 341comes into position adjacent to the first magnetic sensor 271. The firstmagnetic sensor 271 detects the magnetic force, and the first closedstatus is thereby detected.

A second magnet 342 is positioned on other side of the rotation axis 41.The back of a case 342 a holding the second magnet 342 is shown in FIG.16. The case 342 a has an aperture (not shown) on the back of thedisplay screen 31, and the second magnet 342 is exposed from theaperture toward the back of the display screen. Therefore, the secondmagnet 342 has strong magnetic force away from the display screen.

In FIG. 16, a circuit substrate 35 is lifted out of the way to revealthe position of the second magnet 342. However, the circuit substrate 35is arranged in a position in which the back of the case 342 a storingthe second magnet 342 is hidden.

FIG. 17 shows the second unit 30 (display screen 31) rotated by 180° toallow the back of the second unit 30 to face the keyboard 21.

As shown in FIG. 17, when the back of the second unit 30 faces the firstunit 20, the second magnet 342 is moved to a position corresponding tothe second magnetic sensor 272. The material of the back cover of thesecond unit 30 is selected to allow the magnetic force to pass withoutappreciable reduction in intensity, such that when the second unit 30 islaid on the first unit 20 with the back cover facing the first unit, thesecond magnet 342 is positioned adjacent to the second magnetic sensor272, and the second closed status (tablet mode) can be detected.

FIGS. 18A-C shows the second unit 30 opened by 180° relative to thefirst unit 20. FIG. 18A is a left side view, FIG. 18B is a plan view,and FIG. 18C is a right side view.

In the present example, the thickness of the first unit 20 is 22 mm, andthe first magnetic sensor 271 and the second magnetic sensor 272 arepositioned 0.8 mm deeper than the surface of the keyboard of the firstunit 20. The magnetic sensors 271 and 272 are each 2.2 mm thick. Thus,the first magnetic sensor 271 and the second magnetic sensor 272 arepositioned close to the surface of the keyboard within the thickness ofthe first unit 20.

Also in the present example, the thickness of the second unit 30 is 12mm, and the first magnet 341 is arranged at a depth of 2 mm from thesurface of the display screen 31 of the second unit 30. The thickness ofthe first magnet 341 is 5 mm including the case 341 a. Thus, the firstmagnet 341 is positioned closed to the surface of the display screen 31within the thickness of the second unit 30.

The second magnet 342 is positioned 0.8 mm from the back of the secondunit 30, and the thickness of the second magnet 342 is 5 mm includingthe case 342 a. Thus, the second magnet 342 is positioned closer to theback, within the thickness of, the second unit 30.

Therefore, in the first closed status, the first magnet 341 is close tothe first magnetic sensor 271 and applies strong magnetic force to thefirst magnetic sensor 271. In the second closed status, the secondmagnet 342 is close to the second magnetic sensor 272, and appliesstrong magnetic force to the second magnetic sensor 272. Thus, accordingto the embodiment, when the electronic apparatus is closed in either thefirst or second closed status, a strong magnetic force is applied to oneor the other of the magnetic sensors, with a high signal to noise ratio.

In this embodiment, the residual flux density Br of the first magnet 341and the second magnet 342 is Br=0.41 to 0.43 (T). When the first closedstatus is entered, the first magnetic sensor 271 detects the magneticforce of the first magnet 341 when the space between the longestportions (near the engagement unit 25 and the attachment unit 33) fromthe coupling section 40 reaches 15 mm to 30 mm. When the second closedstatus is entered, the second magnetic sensor 272 detects the magneticforce of the second magnet 342 when the space reaches 20 mm to 40 mm.

The first magnetic sensor 271 and the second magnetic sensor 272 areplaced on the side of the coupling section 40 beyond the keyboard 21.Therefore, the wrist of a user is unlikely to be placed near themagnetic sensor in the normal use. This minimizes the possibility that auser with a magnetic bracelet can cause a false detection signal.

[Display Panel Fixed Structure]

FIG. 19 shows the upper right portion of the back cover and the displaypanel of the second unit 30 of the electronic apparatus 10 shown inFIG. 1. In FIG. 19, an antenna 64 and a fixing part 65 indicate thestatus prior to the engagement in a back cover 62, and the display panel61 is also not in final position.

FIG. 20 shows the same portion as FIG. 19, but the antenna 64 and thefixing part 65 in their normal assembled positions. FIG. 21 shows thesame portion as FIGS. 19 and 20, with the antenna 64, the fixing part65, and the display panel 61 all arranged in the normal positions.

The components of the second unit 30 (refer to FIG. 1), i.e., thedisplay panel 61 having the display screen 611 and the back cover 62covering the back of the display panel 61 are shown. The front side ofthe display panel 61 is covered with the front cover 63.

As shown in FIG. 19, the antenna 64 is fixed to the fixing part 65. Thefixing part 65 is used in fixing the antenna 64, and is also used infixing the display panel 61. In this embodiment, the method of fixingthe display panel 61 using the fixing part 65 is mainly explained.

The display panel 61 has a mounting hole 612 for a screw. On the otherhand, a boss 621 having a central screw hole 621 a for fixing thedisplay panel 61 is located on the back cover 62. The boss 621 is offsetfrom the mounting hole 612 of the display panel 61. On the central axisof the mounting hole 612, used when the display panel 61 is in thenormal position, a positioning pin 622 is located on the back cover 62.In addition, a projection 623 is provided on the back cover 62.Furthermore, a boss 624 having a central screw hole 624 a, and a boss625 having a central screw hole 625 a are provided.

The fixing part 65 includes a mounting hole 651 and a positioning hole652 to which the antenna 64 is fixed, and a boss 653 having a screw hole653 a penetrated at its center. The aperture (see FIG. 19) at the bottomof the screw hole 653 a is used as a positioning hole for receiving andengaging the positioning pin 622 of the back cover 62. At its top, thescrew hole 653 a is used for attachment with the mounting hole 612 ofthe display panel 61 by screwing them together.

The fixing part 65 is arranged as shown in FIG. 20. The bottom of thescrew hole 653 a in the boss 653 is for receiving and engaging thepositioning pin 622 (refer to FIG. 19). Thus, the mounting hole 651 ofthe fixing part 65 is arranged on the screw hole 621 a at the center ofthe boss 621 provided for the back cover 62, and the projection 623provided in the back cover 62 is engaged in the positioning hole 652 ofthe fixing part 65. The positioning hole 652 of the fixing part 65 isformed large for loose engagement of the projection 623 of the backcover 62, and the mounting hole 651 of the fixing part 65 is also formedlarge for the diameter of the central screw hole 621 a of the boss 621provided in the back cover 62. Correspondingly, the diameter of thescrew hole 653 a penetrated at the center of the boss 653 of the fixingpart 65 matches the positioning pin 622 of the back cover 62 indimension. Therefore, the screw hole 653 a in the center of the boss 653of the fixing part 65 is arranged in the correct position for thepositioning pin 622 of the back cover 62.

As shown in FIG. 21, the mounting hole 612 (refer to FIG. 20) of thedisplay panel 61 is placed and screwed into the screw hole 653 a of thefixing part 65. At this time, the mounting hole 612 of the display panel61, the screw hole 653 a in the center of the boss 653 of the fixingpart 65, and the positioning pin 622 of the back cover 62 are coaxial.

The boss 621 for fixing the display panel 61 is provided on the backcover 62 in the position off the mounting hole 612 of the display panel61 as described above. However, the positioning pin 622 is set on thesame central axis as the mounting hole 612 of the display panel 61 whenthe display panel 61 is arranged in the normal position on the backcover 62, and the positioning pin 622 is engaged in the positioning hole(aperture at the bottom of the screw hole 653 a in the center of theboss 653) of the fixing part 65, and the mounting hole 612 of thedisplay panel 61 is screwed to the screw hole (aperture at the upperportion of the screw hole 653 a in the center of the boss 653) coaxialwith the positioning hole (aperture at the bottom portion), therebyfixing the display panel 61 in the normal position with high precision.

In the embodiment described above, only one type of the display panel 61is shown, but another type of display panel having a different mountinghole position can be incorporated into the back cover having the samestructure. The other type of display panel is directly screwed into thescrew hole 624 a when a mounting hole is positioned in the same centralaxis as the screw hole 624 a in the center of the boss 624 (refer toFIG. 19) and the display panel is incorporated.

If a boss for screwing the display panel 61 of the type shown in FIG. 19is located in the position of the positioning pin 622 of the back cover62, then the boss would interfere with the display panel of the typewhich directly screws into the screw hole 624 a. Therefore, such adisplay panel cannot be incorporated. Therefore, in the illustratedembodiment, the positioning pin 622 is set in the position correspondingto the mounting hole 612 of the display panel 61, and the screw hole 621a for fixing the display panel 61 to the back cover 62 is provided inthe boss 621 arranged in a different position, and the connections aremade by the fixing part 65. In connecting the fixing part 65, the screwhole 653 a in the boss 653 of the fixing part 65 is registered with thepositioning pin 622 of the back cover 62 as described above, andattachment can be made with almost the same high position precision asthe configuration of directly screwing into the central screw holeprovided to the back cover 62.

When a display panel of the type which directly screws into the centralscrew hole 624 a of the boss 624 is incorporated into the central screwhole 624 a, the boss 653 or a metal fixture having no planar portion forfixture of the boss 653 is used instead of the fixing part 65 with thestructure shown in FIG. 19. This is because the display panel of thetype which directly screws into the central screw hole of the boss 624interferes when a boss is set in the position of the positioning pin 622of the back cover 62, and the spread of the fixing part as describeabove interferes with the incorporation of the display panel.

Another boss 625 shown in FIGS. 19 to 21 is used in fixing the frontcover 63 (refer to FIG. 1).

FIGS. 19 to 21 show the fixed structure of the upper right portion of adisplay panel. The structure at the upper left portion of the displaypanel is almost the same as the structure at the upper right portion,except there is no antenna, and therefore, need not be furtherdescribed.

FIGS. 22 to 25 show the fixed structure of the lower left portion of thedisplay panel.

FIG. 22 shows the back cover; FIG. 23 shows the display panel attachedto the back cover; FIG. 24 shows another type of fixing part for fixinganother type of display panel; and FIG. 25 shows another type displaypanel different from the display panel shown in FIG. 23, attached usingthe fixing part shown in FIG. 24.

As shown in FIG. 23, the back cover 62 is provided with a boss 626having a central screw hole for screwing a fixing part 66, and is alsoprovided with two positioning pins 627 and 628. The back cover 62 isalso provided with other boss 629 having a central screw hole 629 a andprojection 630. They are used for attaching other parts as describedlater, and are not related to mounting the display panel.

The positioning pin 627 is used to fix a display panel including amounting hole positioned on the same central axis as the positioning pin627. The positioning pin 628 is used to fix a display panel in which amounting hole is arranged on the same central axis as the positioningpin 628.

The fixing part 66 shown in FIG. 22 has a mounting hole which hasalready accepted a screw and, therefore the mounting hole is hidden fromview. A positioning hole 661 is engaged with the positioning pin 627.The part 66 includes a screw hole 662 to which the mounting hole of thedisplay panel is screwed. A fixing part 66 has a bent portion 66 ahaving two plates bent to face each other, with the positioning hole 661formed on the lower plate, and the screw hole 662 is formed in the upperplate. The screw hole 662 is on the same central axis as the positioninghole 661. In the fixing part 66, the diameter of the positioning hole661 matches the diameter of the positioning pin 627, and the screw hole662 can be positioned with high position precision.

FIG. 23 shows the display panel 61 in which the mounting hole is screwedto the screw hole 662 of the fixing part 66 shown in FIG. 22, and themounting hole (already screwed, and hidden below the screw) of thedisplay panel 61, the screw hole 662 of the fixing part 66 shown in FIG.22, the positioning hole 661, and the positioning pin 627 of the backcover 62 are all on the same central axis, thereby screwing the displaypanel 61 with high position precision.

As shown in FIG. 23, other parts are arranged on another boss 629provided on the back cover 62 and the projection 630 (refer to FIG. 22),and the front cover 63 (refer to FIG. 1) is further arranged on them.The front cover 63 is screwed to the screw hole 629 a of the boss 629with the other parts.

The fixing part 67 shown in FIG. 24 is a fixing part for fixing anothertype of display panel. As with the fixing part 66 shown in FIG. 22, amounting hole (as in the case shown in FIG. 22, it is already screwed,and the mounting hole is hidden below the screw) screwed into thecentral screw hole (not shown) of the boss 626 of the back cover 62 isprovided. The fixing part 67 shown in FIG. 24 includes a cutout 671 intowhich the positioning pin 627 is engaged to position the fixing part 67.Furthermore, the fixing part 67 is provided with a boss 672 having acentral screw hole 672 a. The aperture of the bottom portion of thescrew hole 672 a of the boss 672 is used as a positioning hole in whichthe positioning pin 628 (refer to FIG. 22) provided in the back cover 62is engaged. The aperture at the upper portion shown in FIG. 24 of thescrew hole 672 a is used as a screw hole for screwing the mounting holeof a display panel.

FIG. 25 shows a display panel 61′ in which a mounting hole is screwed tothe screw hole of the boss 672 of the fixing part 67 shown in FIG. 24.The mounting hole (already screwed and is hidden below the screw) of thedisplay panel 61′, the screw hole 672 a of the boss 672 of the fixingpart 67 shown in FIG. 24, and the positioning pin 628 of the back cover62 are all on the same central axis, and the display panel 61′ is fixedwith high position precision.

No boss is provided in the positions of the two positioning pins 627 and628 of the back cover 62 shown in FIG. 22 for the same reason as thereis no boss in the position of the positioning pin 622 shown in FIG. 19.If a boss is set in the position of the positioning pin 627 shown inFIG. 22, it would interfere with the display panel 61′ such that thedisplay panel 61′ could not be incorporated. Likewise, if a boss is setin the position of the positioning pin 628 shown in FIG. 22, it wouldinterfere with the display panel 61 shown in FIG. 23, such that thedisplay panel 61 could not be incorporated. In this embodiment, thepositioning pins 627 and 628 are provided on the same central axis asthe mounting hole of the display panel, and either the positioning pin627 is engaged in the positioning hole 661 of the fixing part 66 shownin FIG. 22, or the positioning pin 628 is engaged at the bottom of thescrew hole 672 a of the boss 672 of the fixing part 67, as shown in FIG.24. Therefore, either of the display panels 61 and 61′ can be mountedwith high position precision although a boss is set in a positiondifferent from the position of the mounting hole of the display panel.

[Arrangement of External Coil]

FIG. 26 shows a part of a bottom cover 71 of the first unit 20 of theelectronic apparatus 10 shown in FIG. 1, and a circuit substrate 72arranged on the bottom cover.

The first unit 20 of the electronic apparatus 10 shown in FIG. 1includes the bottom cover 71 shown in FIG. 26, the circuit substrate 72arranged on the bottom cover 71 and other parts not shown in theattached drawings, and the upper cover 73 (refer to FIG. 1) includingthe keyboard 21 (refer to FIG. 1), etc.

As shown in FIG. 26, the bottom cover 71 is provided with some apertures711 a, 711 b, and 711 c and air holes 721 a, 721 b, and 721 c forcirculation of air.

The circuit substrate 72 includes various circuits, and is, for exampleillustrated here, four DC-DC converters. FIG. 26 shows a total of fiveexternal coils 721 for four DC-DC converters together with many othercircuit units.

FIG. 26 shows the inner side of the bottom cover 71, and the side of thebottom cover of the circuit substrate 72. This circuit substrate 72 isarranged on the bottom cover 71 such that the face shown in FIG. 26faces the bottom cover 71 as indicated by arrow in FIG. 26.

FIG. 27 is a rough block diagram of the DC-DC converter.

Power supply of input voltage Vin of 19V is applied when the electronicapparatus 10 is connected to an AC power supply, or power supply of thevoltage of 10.8V is applied when a battery (not shown) is used. Ineither case, the power supply voltage is input to a gate circuit 722.The gate circuit 722 turns the input power on and off at the frequencyof, for example, about 250 to 400 kHz under the control of an externalcoil 721, uses an external coil 721 to generate predetermined DC voltageVout. In the case of a DC-DC converter requiring large electric power,the gate circuits 722 and the external coils 721 are connected inparallel. The DC-DC converter itself is a well known technique, and nofurther explanation about the DC-DC converter is required.

As described above, the display panel 61 (refer to FIGS. 19 to 21) has apen inputting function, and communicates with the pen at a highfrequency. Thus, it is susceptible to interference from external rf.Specifically, rf in the range of 270 kHz to 300 kHz, may causeinterference with pen operation. Since the DC-DC converter operates inthis general frequency range, the external coil 721 functions as anantenna to generate rf noise that potentially could interfere with theopen operation.

When the electronic apparatus 10 is operated in the notebook PC mode,the second unit 30 (display screen 31) is open and, therefore, separatedfrom the circuit substrate of the first unit 20. Thus, rf from the coilsin the first unit is unlikely to interfere with the display screen 31.In the tablet mode, although the two units are in contact, rf from thecoils in the first unit is also unlikely to interfere with the displayscreen 31 because the circuit substrate in the first unit 20 ispositioned on the back of the display screen 31 and thus any rf from thecircuit substrate in the first unit 20 must penetrate the base unit toreach the display screen 31. However, in the first closed status, withthe display screen 31 lying on directly on the first unit, a keyboardand display monitor can be externally connected such that the electronicapparatus may be operated in this mode. When used in this manner, thereis nothing to shield the rf from the circuit substrate from reaching thedisplay screen 31.

In this situation, as shown in FIG. 26, the external coil 721 of theDC-DC converter is loaded on the side facing the bottom cover 71 of thecircuit substrate 72. The external coil 721 generates strong noise onthe side loaded with the external coil 721, but the noise transmitted tothe reverse side of the surface loaded with the external coil 721 on thecircuit substrate 72 is substantially attenuated. In this embodiment,the external coil 721 of the DC-DC converter is loaded on the surfacefacing the bottom cover 71 of the circuit substrate 72. Therefore,although the electronic apparatus is used in the closed status as shownin FIG. 5, interference due to rf noise from the external coil 721 canbe prevented.

In this embodiment, all the five external coils 721 are loaded onto thesurface facing the bottom cover 71 of the circuit substrate 72. However,when the frequency used in the DC-DC converter is substantiallydifferent from the 270 kHz to 300 kHz which is the frequency of easilycausing a malfunction of the display panel 61, it is not necessary toposition all or some of the coils on the surface facing the bottom cover71 of the circuit substrate 72. In this embodiment, two of the fiveexternal coils 721 are those used in the DC-DC converter operatingaround 350 kHz and 400 kHz, and these two the external coils may not bepositioned on the surface facing the bottom cover 71 of the circuitsubstrate 72, that is, can be arranged on the keyboard 21 side (refer toFIG. 1) of the circuit substrate 72.

FIG. 28 shows the relative positions of the bottom cover and theexternal coils viewed from the bottom cover.

The five external coils 721 on the circuit substrate 72 are arranged assurrounding the air hole 712 a of the bottom cover 71 because the DC-DCconverter processes electric power and thus the external coil 721generates heat. When a heat generating external coil 721 is aligned withthe air holes in an array 712 a, the flow of air is hindered and theheat dissipation is degraded. Therefore, the five external coils 721 arepreferably arranged to surround the air holes 712 a, not immediatelybelow (above) the air hole 712 a, such that the flow of air is notimpeded and necessary cooling can be performed.

[Protection of the Optical Disk]

FIG. 29 is a block diagram showing the control of the optical disk drive26 (refer to FIGS. 1 and 2) of the electronic apparatus 10 shown in FIG.10.

FIG. 29 shows: a main system 81 provided with a control unit having aCPU, memory, etc.; a display section 82 for displaying an imagedescribed later on the display screen 31 shown in FIG. 1, in response toan instruction of the main system 81; a open/close detection section 83for discriminating the open status (refer to FIG. 1), the first closedstatus (refer to FIG. 5), and the second closed status (refer to FIG. 7)using the magnetic sensors 271 and 272, and the magnets 341 and 342(refer to FIG. 16), and transmitting them to the main system 81; a portreplicator connection detecting section 84 for detecting the attachmentof the first unit 20 to the port replicator 50 shown in FIG. 3 andtransmitting the information to the main system 81; and the optical diskdrive 26 operating under the control of the main system 81. The portreplicator connection detecting section 84 detects theconnection/disconnection between the connector 51 provided in the portreplicator 50 shown in FIG. 3 and the connector (not shown) for couplingwith the connector 51 and provided at the bottom of the first unit 20 bydetecting the electrical disconnection of one pin.

As shown in FIG. 29, the optical disk drive 26 includes a drive controlsection 91 for control of the entire optical disk drive; a motor 92 forrotating and stopping an optical disk such as an inserted CD, DVD, etc.under the control of the drive control section 91; as shown in FIG. 1and FIG. 2, the eject button 262 for issuing an instruction to open, asshown in FIG. 2, the optical disk drive in the status shown in FIG. 1;and an ejection mechanism 93 for projecting the tray of the optical diskdrive 26 outward as shown in FIG. 2 under the control of the drivecontrol section 91. In the electronic apparatus shown in FIG. 1, a driveof a tray loading system is adopted as an optical disk drive, but it isobvious that a drive of any other systems using no tray can be appliedto the present invention. The present invention can also be applied to adrive for any other storage media such as, in addition to an opticaldisk, a floppy disk, MO, etc.

In the main system 81, according to the detection results of theopen/close detection section 83 and the port replicator connectiondetecting section 84, it is determined whether or not the electronicapparatus 10 is in the tablet mode as shown in FIG. 7.

In this embodiment, if the port replicator connection detecting section84 detects that the status is changed from the status in which theelectronic apparatus 10 is connected to the port replicator 50 as shownin FIGS. 4 and 5 to the status in which it is disconnected from the portreplicator 50 as shown in FIG. 1, and if the open/close detectionsection 83 detects the second closed status as shown in FIG. 7, then itis determined that the tablet mode is entered. If the open/closedetection section 83 does not detect the second closed status as shownin FIG. 7 or the port replicator connection detecting section 84 detectsthe connection to the port replicator 50 as shown in FIG. 3, then it isdetermined that the tablet mode is terminated. For more securityrelating to the control of the optical disk drive 26, it is determinedthat the tablet mode is entered by the detection of the port replicatorconnection detecting section 84 about the disconnection from the portreplicator or the detection of the open/close detection section 83 aboutthe second closed status as shown in FIG. 7 in controlling the opticaldisk drive 26.

When the main system 81 determines that the tablet mode is entered orthe tablet mode is terminated, the determination result is transmittedto the drive control section 91 of the optical disk drive 26. Uponreceipt of the information from the main system 81 that the tablet modeis entered, the drive control section 91 stops the rotation of the motor92 if it is working, prohibits the rotation, and prohibits the openingoperation of the optical disk drive by the ejection mechanism 93 asshown in FIG. 2 even if the eject button 262 is pressed.

When a notification that the tablet mode is terminated is received fromthe main system 81, the drive control section 91 rotates the motor 92 atthe access request from the main system 81 to access an optical disk, oraccepts the operation of the eject button 262 to instruct the ejectionmechanism 93 to open the optical disk drive as shown in FIG. 2.

The main system 81 also allows the display section 82 to display thatthe access to an optical disk is prohibited.

FIG. 30 is a rough flowchart of the program operating in the CPU of themain system when the detection result is changed.

The program operates when the open/close detection section 83 shown inFIG. 29 detects the opened/closed status or the port replicatorconnection detecting section 84 detects the attachment status of theport replicator 50.

The program first determines whether or not the tablet mode is entered(step a). If the tablet mode is entered, the notification that thetablet mode is entered is issued, that is, an instruction to disable therotation drive of an optical disk by the motor 92 (step b1) and todisable ejection (step b2) is issued, and an instruction to display theinformation that the optical disk drive 26 is inoperable (step b3) isissued.

If it is determined in step a that the tablet mode is not entered, thenotification that the tablet mode is not entered is issued, that is, aninstruction to release the prohibition of the drive of an optical diskby the motor 92 (step c1) and to release the prohibition of ejection(step c2) is issued, and an instruction to erase the information thatthe optical disk drive 26 is inoperable (step c3) is issued.

Described below are various screens displayed when the use of theoptical disk drive 26 is prohibited and when the prohibition isreleased.

FIG. 31 shows the setting screen on which whether or not the function ofprohibiting the use of the optical disk drive 26 and the function ofreleasing the prohibition is used.

In this embodiment, the function according to the flow shown in FIG. 30can be used by checking the column of “Lock CD/DVD drive when the unitis in tablet mode”, and then pressing the “OK” button.

FIG. 32 shows an example of the screen displayed when the optical diskdrive transfers to the use disabled status.

In this embodiment, an icon indicating that the optical disk drive is inthe use disabled status is displayed, and the indication of havingentered the use disabled status is displayed for a certain period oftime. FIG. 33 shows an example of the screen displaying that the opticaldisk drive is currently in the use disabled status.

Part (A) of FIG. 33 shows an icon indicating that the optical disk driveis currently in the use disabled status. When the icon is pointed to bythe cursor on the display screen, the explanation of the icon isdisplayed for a predetermined time as indicated by part (B) of FIG. 33.

1. An electronic apparatus that includes a display panel having a display screen and a cover for covering the display panel, wherein: the display panel has a first mounting hole for accepting a display fastener; the cover has a first boss on which a first fastener hole is formed and which is formed in a position off center with respect to the first mounting hole, and the cover further has a positioning pin that projects on the same central axis as the first mounting hole; and the electronic apparatus includes a fixing member in which are formed a second mounting hole that is fixed by a first fastener to the first fastener hole of the first boss, a positioning hole in which the positioning pin is engaged, and a second fastener hole that is formed on the same central axis as the positioning hole and fixed by the display fastener to the first mounting hole.
 2. The electronic apparatus according to claim 1, wherein the cover is capable of accepting a display panel having a third mounting hole that is formed in a position different from the first mounting hole instead of the first mounting hole, and the cover includes a second boss that has a third fastener hole on the same central axis as the third mounting hole.
 3. The electronic apparatus according to claim 1, wherein the fixing member has a bent portion having two plates bent to face each other, and the positioning hole is formed in the lower plate of the bent portion and the second fastener hole is formed in the upper plate of the bent portion.
 4. The electronic apparatus according to claim 1, wherein the fixing member has a through hole of which lower portion is used as the positioning hole and of which upper portion is used as the second fastener hole.
 5. A display panel fixed structure that is used in an electronic apparatus provided with a display panel, the display panel including a display screen and a cover for covering the display panel, wherein: the cover has a first boss on which a first fastener hole is formed and which is formed in a position off center with respect to a first mounting hole formed in the display panel for accepting a first fastener, and the cover further has a positioning pin that projects on the same central axis as the first mounting hole; and the display panel fixed structure includes a fixing member in which are formed a second mounting hole that is fixed by the first fastener to the first fastener hole of the first boss, a positioning hole in which the pin projection is engaged, and a second fastener hole that is formed on the same central axis as the positioning hole and fixed by a display fastener to the first mounting hole.
 6. The display panel fixed structure according to claim 5, wherein the cover is capable of accepting a display panel having a third mounting hole that is formed in a position different from the first mounting hole instead of the first mounting hole, and the cover includes a second boss that has a third fastener hole on the same central axis as the third mounting hole.
 7. The display panel fixed structure according to claim 5, wherein the fixing member has a bent portion having two plates bent to face each other, and the positioning hole is formed in the lower plate of the bent portion and the second fastener hole is formed in the upper plate of the bent portion.
 8. The display panel fixed structure according to claim 5, wherein the fixing member has a through hole of which lower portion is used as the positioning hole and of which upper portion is used as the second fastener hole. 